Olive oil is a staple ingredient of Greek food. Stews made of green bean, eggplant, potato or zucchini are usually cooked in olive oil. In addition to being used as a key cooking ingredient in Greek food, olive oil has been used as a sacrifice to the gods and to bathe in. Olive trees are native to the Greek landscape and it was natural that the early Greeks would pick the olives. Soon, the Greeks discovered that pressing olives released oil. The Greeks stored this oil in pottery containers and were able to use olive oil in cooking Greek food year round regardless of the growing season.